Lamp socket



F. H. WESTON June 24, 1.930.

LAMP SOCKET Filed March 29, 1928 Fug. 4.

Inventor": Fredevick H. We sboTw His Attorney Patented June 24, 1930 UNITED STATES PATENT OFFICE FREDERICK H. WESTON, OF BRIDGEPORT, CONNECTICUT, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK LAMP SOCKET Application filed March 29, 1928. Serial No. 265,723.

This invention relates to electric lighting and more especially to incandescent lamp sockets. The object of my invention is the provision of an improved lamp socket which shall have the conductive metal contacts permanently secured within an outer shell of insulation, which shall be strong and durable, and which shall be composed of few and simple parts easily assembled and of low 1 manufacturing cost.

One embodiment of my invention is shown in the accompanying drawing in which Fig. 1 is an axial section of a complete socket; Fig. 2 is a transverse section thereof on line 22 of Fig. 1; Fig. 3 is an axial section of a complete socket embodying a modified detail; Fig. l is a transverse section on line 1-4 of Fig. 3 with the center contact broken; Fig. 5 is an enlarged fragmentary perspective view showing the relation of the screw shell flange to the outer shell of insulation, and Fig. 6 is a similar view showing the relation of the screw shell to the insulating disk carried thereby.

As shown in the drawing, the outer shell 1 is of elastic insulating material, with a substantially cylindrical side wall 2 and a frusto-conical lower end wall 3 apertured for the passage of lead wires and as shown in Fig. 1 provided externally with a crown flange 4. The inner surface of the side wall 2 is provided with a plurality of spaced longitudinal A-shaped ribs 5 which extend from the end wall to adjacent the open end where they taper off.

, The current-carrying parts comprise a screw shell 6 of relatively thin elastic metal with its lower end closed by an insulating disk 7 held in place by spurs 8 and an end flange 9 on the shell, and a spring center contact 10 secured to the inner side of the insulating disk by an upset eyelet 11. The upper end 12 of the screw shell 6 is flanged or belled outwardly so that its diameter corresponds with the inner diameter of the outer insulating shell 1, while the maximum outer diameter of the screw-threaded portion of the metal shell 6 is such as to engage the ridges of the ribs 5 in the insulating outer shell.

In assembling the parts of my socket, lead wires 13 and 14 are respectively soldered to the screw shell 6 and to the metal eyelet 11 of the center contact and the free ends passed through the aperture .in the end wall 3 of the insulating outer shell and then upon forcing home of the metal screw'shell 6 in the insulating outer shell, it will be centrally positioned by the ribs 5 engaging the outermost diameter of the screw-threaded portion of the shell 6, while the belled upper end 12 becomes indented by its passage in contact with the ribs 5, and by reason of the elasticity of both the metal screw shell 6 and the insulating outer shell the belled 'end 12 of the former becomes permanently locked to the inner surface of the latter both rotarily and longitudinally so that they cannot be disengaged in spite of the differences in coeflicients of expansion of the insulating material and the metal contact.

To make the socket weatherproof, the recess within the crown flange 4 may be filled with insulating pitch or other sealing material.

In sockets not intended to be installed out of doors, the crown flange 4 may be omitted, as indicated in Fig. 3, and in order to insure against the lead wires becoming shorted upon being twisted together the insulating disk 7 is provided with a second aperture 15 through which the lead wire 14 to the center contact and its braided insulation may be passed and then the stripped end bent over and soldered within the eyelet 11 of the center contact, thus holding the insulation of the wire from retracting and exposing the bare metal below the insulating disk.

While I have shown and described the best embodiment of the invention known to me,I do not desire to be restricted thereto.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. A lamp socket comprising an insulating outer shell of slightly elastic material provided internally with longitudinal ribs, and a metal contact shell disposed within said outer shell and having interlocked engagement with the ribs thereof, whereby said parts are permanently held in fixed relation both axially and rotatably.

2. A lamp socket comprising an insulating outer shell of slightly elastic material having a substantiall cylindrical cavity with longitudinal ribs on the wall thereof tapered at their outer ends, and a deformable metal contact shell forced into said cavity and in interlocking engagement with said ribs, whereby said parts are permanently held in fixed relation both axially and rotatably.

3. A lamp socket comprising an insulating outer shell provided internally with longitudinal ribs, and a metal screw shell cont; ct having an external flange indented about and firmly engaging said ribs.

4. A lamp socket comprising an insulating outer shell having a substantially cylindrical cavity with A-shaped longitudinal ribs on the wall thereof, and a screw shell contact having a bell-shaped flange at the outer end thereof in which said ribs are embedded upon assembly of said screw shell within the cavity of said outer shell.

5. A lamp socket comprising a screw shell contact, an insulating disk secured therein and provided with an apertured center contact and a parallel aperture adjacent thereto, said screw shell having an insulated lead wire attached thereto, and a second insulated lead wire extending with its insulation through said parallel aperture in the disk and soldered in the aperture of said center Contact.

In witness whereof, I have hereunto set my hand this 27th day of March, 1928.

FREDERICK H. WESTON. 

